Silencer device for firearm

ABSTRACT

The invention relates to a silencer device for a firearm, in particular for a rifle or another long or short firearm, and to a silencing method, said device comprising: a flap mechanism ( 10 ) comprising at least one closing flap ( 10 ) mounted transversely to the axis on the barrel ( 42 ) of the firearm in order to temporarily seal the barrel after ammunition has passed through and to prevent the passage of the combustion gases and the sound wave towards the mouth of the barrel when a shot is fired; and an actuating unit ( 31,34,35 ) comprising a mobile part ( 31 ) arranged axially on the barrel of the firearm in order to move a control mechanism ( 6 ), where the mobile part ( 31 ) axially comprises an inner borehole for allowing ammunition to pass through, the control mechanism ( 6 ) includes at least one amplitude lever arm ( 8 ) pivotably mounted on a pivot ( 7 ) attached to the barrel, and each amplitude lever arm ( 8 ) is respectively coupled to a closing flap ( 10 ), the mobile actuating unit ( 31,34,35 ) cooperating with the control mechanism ( 6 ) to allow a transverse movement of said at least one closing flap ( 10 ) between an open position in which the flap mechanism ( 10 ) allows ammunition to pass towards the mouth of the barrel ( 42 ) and a closed position preventing the passage of the combustion gases and the sound wave after the ammunition has passed through; and an exhaust unit ( 11, 21 - 27 ) including at least one exhaust pipe ( 11, 21 ) arranged on the barrel upstream from the closing flap mechanism ( 10 ) in order to redirect the combustion gases and the sound wave and allow them to leave the barrel.

The present invention relates to a silencer device for a firearm, inparticular for a rifle or another long or short firearm, and to a methodfor silencing a firearm.

TECHNICAL FIELD

In accordance with a first aspect, the present invention relates morespecifically to a silencer for a firearm, such as a rifle or anotherlong or short firearm.

In accordance with a second aspect, the invention proposes a method forsilencing a firearm, in particular a rifle or another firearm, when ashot is fired.

In accordance with a third aspect, the invention proposes a firearm, inparticular a rifle, including an improved silencer device.

PRIOR ART

With regard to the prior art, there exists the conventional silencer,also referred to as a noise regulator, which can be added to a firearm,gas weapon or air gun and which is aimed at mechanically reducing noise.

By way of example, publication WO 96/03612 discloses a noise moderatingdevice for rifles for clay pigeon shooting or other recreationalactivities, having superposed barrels of all calibres. This firearmsilencer is formed by a tubular encasement that is mounted on the barrelof the gun and includes an annular decompression chamber to the rear ofsaid tubular encasement, as well as a series of internal cross bafflesheld by spacers and equipped with orifices allowing the passage of thelead shots and the wad. The silencer is intended to dampen the noise andthus reduce noise pollution.

Publications WO 2011/035111 A1 and WO 2014/000805 disclose furtherexamples of firearm silencers, in particular for automatic rifles oranother long or short firearm, including a silencer mounted on thebarrel of the firearm, wherein a muzzle brake, which can be connected byscrewing to the silencer, is fixed to the barrel.

CONVENTIONAL SILENCER

A conventional silencer or noise regulator is a device that can be addedto a firearm, gas weapon or air gun in order to reduce the noise andlight flash produced thereby when a shot is fired, thus making theweapon in question more stealthy.

To do this, the silencer generally takes the form of a cylindrical tubeable to be adapted to the mouth of the barrel, and the internalmechanism of said tube, which mechanism varies depending on theammunition used, makes it possible to reduce the pressure of gases usedto propel the projectile, so as to mitigate their release into theatmosphere to the greatest possible extent.

Since the silencer merely slows the gas at the outlet of the barrel, ithas no effect on the noise produced by the passage of the projectile atsupersonic speed (speed greater than the speed of sound, which isapproximately 340 m/s in air at 15° C.), which, by exceeding the soundbarrier, in turn produces detonation noise over its path. The phenomenonis sensitive above all on initial high-speed calibres, such as 5.56 mm.For some cartridge calibres, in particular for handguns, there existsubsonic munitions created specifically for use with a silencer in orderto minimise the sound of a shot being fired.

A silencer is above all a comfort tool because it reduces the muzzlewave of a firearm. This muzzle wave is the cause of ENT traumas, in theear, nose and throat area, which the usual means (ear plugs, helmets,etc.) cannot provide protection against.

It should be noted that the two main factors affecting the value of thespeed of the sound are the density and spring rate (or compressibility)of the propagation medium:

The lower the density and compressibility of the medium, the morequickly the sound will propagate. These two parameters change from onemedium to the next. In helium, the compressibility of which is almostequal to that of air, but the density of which is much lower under thesame temperature and pressure conditions, the speed of the sound isalmost three times greater than in air. In a gas at atmosphericpressure, the speed of the sound is much lower than in a liquid:although the density of the gas is much lower, the gas is almostinfinitely more compressible than the liquid (which is often consideredincompressible).

For example, the sound propagates exactly at 1,482.343 m/s in pure waterat 20° C., approximately at 340 m/s in air at 15° C., and at around1,500 m/s in seawater.

The effectiveness of silencers is relative: the noise reducer suppressesthe muzzle wave and consequently the subsequent detonation and makes thenoise thereof more diffuse whilst suppressing the flame at the mouth ofthe weapon. The term noise regulator is sometimes used; the performanceof this type of device varies greatly depending on the type of noisereducer employed and the weapon used. The shorter the distance at whichthe shot can be heard, the more difficult it is to identify it as a shotfrom a firearm, and the more difficult it is to locate due to thedistortion of the noise and also the absence of a visible flame. Themagnitude of the noise is reduced by the order of 25 to 35 dB in thecase of an assault rifle, that is to say it is 115 to 125 dB (comparableto a pneumatic drill) instead of 150 dB. The conventional silencers,whilst being provided in different forms and utilising differenttechniques, are nevertheless all rather similar. They are generallyconstituted by sleeves that are fixed to the end of the barrel, eitherby a bayonet system or by a threaded screw.

These sleeves, of substantial size, include a plurality of gas expansionchambers in their interior, which make it possible to attenuate thenoise of the detonation with varying levels of success. The projectile,the gases and the residual sound wave exit via the mouth.

Their faults are as follows: significant weight (several hundred grams,perhaps more than a kilo), large dimensions, imbalance of the weapon(the nose drops), impossibility of use in double-barrel weapons andalso, for the most part, with shot ammunition.

In addition, since the diameter of the holes separating the variouselements of the silencer through which the projectiles pass is muchlarger than the calibre, they allow some of the gases to escape to thefront of the projectile, thus interfering with the accuracy of theprojectile and reducing the speed thereof approximately by 4 to 6 m/s.

The conventional silencer is costly, is difficult to maintain (it mustbe completely disassembled, part by part, for cleaning) and, for somerifle models, its lifetime is less than 800 shots.

As it passes through the various baffles, the projectile allows thegases behind it to expand in the cells, thus reducing the magnitude ofthe sound wave.

The effectiveness of a silencer of this kind is down to two factors: itsdimensions (the larger it is, the more it damps), and the distanceseparating it from the combustion chamber (the greater the distance, thegreater the effectiveness). Since the silencer is situated at the end ofthe barrel, the longer the length of said barrel, the more effective thesilencer will be, therefore. Furthermore, there is practically no effectat all if the silencer is used with weapons having a very short barrel,unless the silencer is greatly oversized.

In this type of silencer the reduction of the noise is dependent on thesize of the chambers (cells). The noise normally produced by thedetonation of a firearm is approximately from 120 to 170 dB. Thus, asudden noise or extended exposure to excessive ambient noise (beyond 100dB) may cause a temporary or permanent change to a person's hearing.

In addition, implementation difficulties are also encountered inparticular for certain conventional silencers or those that are noteffective enough to reduce the noise when a shot is fired with thefirearm, which results in certain problems.

SUMMARY OF THE INVENTION

It is therefore clear that there is a need for a system which, to alarge extent, makes it possible to overcome the above-describeddisadvantages encountered in the prior art.

The object of the invention is to provide an improved silencer devicefor a firearm, in particular for a rifle or another long or shortfirearm.

Whereas a conventional silencer, also referred to as a noise regulator,endeavours to mechanically reduce noise, the aim of the presentinvention is therefore to propose a device for eliminating andcompletely preventing the noise produced when a shot is fired byallowing it to deplete naturally, thus resulting in greater stealth.

The aim of the device is therefore to inhibit the sound wave (the noise)generated by the ammunition of a firearm.

This object is achieved, in accordance with the invention, in that thesilencer device for a firearm has the features of the characterisingpart of claim 1.

More particularly, to this end, in accordance with the invention, thisaim is achieved in that the aforementioned silencer device comprises:

-   -   a flap mechanism (10) comprising at least one closing flap (10)        mounted across the axis on the barrel (42) of the firearm in        order to temporarily seal the barrel after the ammunition has        passed and to prevent the passage of the combustion gases and        the sound wave towards the mouth of the barrel when a shot is        fired,    -   an actuation unit (31, 34, 35) including a mobile portion (31)        disposed axially on the barrel of the firearm so as to move a        control mechanism (6), the axially mobile portion (31) having an        inner bore suitable for allowing the passage of ammunition,    -   the control mechanism (6) including at least one amplitude lever        arm (8) pivotably mounted on a pivot (7) attached to the barrel,        each amplitude lever arm (8) being coupled to a separate closing        flap (10),    -   the mobile actuation unit (31, 34, 35) engaging with the control        mechanism (6) to allow a transverse movement of said at least        one closing flap (10) between an open position, in which the        flap mechanism (10) allows ammunition to pass towards the mouth        of the barrel (42), and a closed position, which prevents the        passage of the combustion gases and the sound wave after the        ammunition has passed, and    -   an exhaust unit (11, 21-27) including at least one exhaust pipe        (11, 21) arranged on the barrel upstream from the closing flap        mechanism (10) in order to redirect the combustion gases and the        sound wave and allow them to be discharged from the barrel.

Thus, in order to achieve this aim, the barrel is temporarily sealedwith the aid of the closing flap mechanism just after the passage of theprojectile, and the combustion gases and the sound wave are redirectedtowards an expansion space for their final processing.

Preferably, in one embodiment of the invention, the actuation unitincludes a mobile portion (31) of the barrel, said portion being movedby the projectile as soon as said projectile has fully passed the flaps,and extended by a rod connected to the control ring.

In accordance with the invention, in order to assure the motivity of thesystem as a whole, a small portion of the barrel is made mobile. Theportion can be an end or middle portion.

Preferably, as the projectile passes through the mobile part (31), thepart is pushed axially forwards in the downstream portion (38) of thebarrel by the pressure of the gases within the barrel. The axialmovement of the mobile part (31) causes the flaps to close by means ofthe coupling of the amplitude lever arm (8) to the closing flapmechanism (10). In principle, in firearms manufactured directly with thedevice incorporated, the mobile part will be a middle part at the veryleast on long firearms.

In the case in which the mobile portion is a middle portion, it isjoined to the portion of the barrel exiting from the flap seats and theend portion of the barrel.

The interior of the barrel (in which the projectile moves) isdeconstructed into three perfectly aligned portions.

Preferably, the mobile part has a covering portion and a coveredportion. In its covering portion, the mobile portion covers the barrel,and in its covered portion it is covered by the final portion of thebarrel. The length of the portion of the barrel that passes through theseat of the flaps in principle has a fixed length equal to the length ofthe bullet.

In its covered portion, the mobile part reproduces the portion of thebarrel that exits from the flaps and is covered in turn. The final partof the barrel that is mounted on the seats of the flaps contains themobile part in full. The final portion of the barrel can be very short.

In the case in which the mobile portion is an end portion, said finalportion forms the mouth of the barrel. This is the same configurationfor BB guns and for chokes. Whereas for BB guns the mobile portion ispreferably cylindrical and rather short, for shotguns the mobile portionpreferably has the forms, the patterns and the length of a traditionalchoke.

The control mechanism preferably includes a guide and transmission ringcapable of sliding over the barrel, the ring cooperating with the rod ofthe mobile portion so as to transmit the movement to the lever arms.

The closing flap(s) is/are preferably disposed in a seat placed acrossthe axis of the barrel and are of a predetermined length and, if thereare two flaps, are slightly offset from one another along the axis ofthe barrel, such that they partially overlap one another in the closedposition without contacting one another.

In one embodiment of the invention each flap includes an opening forreceiving the end of the amplitude lever arm so as to transmit thepivoting movement of the amplitude lever and actuate the flap in atransverse direction relative to the axis of the barrel.

The guide ring preferably further comprises two wedge-shaped supportparts having an angled-edge surface directed towards the flaps forenabling the actuation of the lever arms pivoting on the pivots and theclosure of the flaps.

In one embodiment of the invention the control mechanism includes afirst return spring associated with the guide ring such that said guidering can resume its initial position, lowering the pressure of thegases.

In a preferred embodiment of the invention the exhaust unit alsocomprises an expansion space connected to said at least one exhaust pipeso as to receive the gases transported by said at least one exhaustpipe, the expansion space including vents for discharging the combustiongases from the expansion space.

The expansion space preferably comprises an inner tube connected toflaps capable of sealing the vents, in which tube the gases enter theexpansion space via an opening made in the inner tube once said tube hasbeen pushed to its end position and has thus sealed the vents, and, asthe pressure reduces, the inner tube resumes its starting position owingto a return spring, thus allowing the combustion gases to be dischargedfrom the expansion space via the vents when the sound wave has depletednaturally.

In a preferred embodiment of the invention the mobile portion of thesubstantially cylindrical actuation unit joins a portion of the barrelthat passes through the seat of the closing flaps and an end portion ofthe barrel, and includes a covering portion and a covered portionseparated by a shoulder, the covering cylindrical portion being able tocover the portion of the barrel that passes through the seat of theflaps, and the covered cylindrical portion being able to be covered bythe end portion of the barrel.

Preferably, the final portion of the barrel comprises a receptacleincluding a first cylindrical portion able to receive the coveringportion of the mobile part, and a second cylindrical portion of asmaller diameter able to receive the covered portion of the mobile part,the first cylindrical portion and the second cylindrical portion of theend portion being separated by a shoulder.

Preferably, the first cylindrical portion of the end portion is longerthan the covering cylindrical portion of the mobile part so as to allowthe axial movement of the mobile part, the second cylindrical portion ofthe end portion being substantially the same length as the coveredcylindrical portion of the mobile part.

Preferably, the covering portion of the mobile part has an innerdiameter corresponding to the outer diameter of the portion of thebarrel that passes through the seat, and has an outer diametercorresponding to the inner diameter of the first cylindrical portion ofthe end portion.

In a further preferred embodiment of the invention, the mobile portionof the substantially cylindrical actuation unit forms the end portion ofthe barrel and includes a covering portion and a final portion separatedby a shoulder, the covering cylindrical portion of the mobile part beingable to cover a portion of the barrel that passes through the seat ofthe closing flaps, and the end portion forming the mouth of the barrel.

Preferably, the covering portion of the mobile part comprises areceptacle including a cylindrical portion capable of receiving thecylindrical portion of the barrel that passes through the seat of theflaps and of enabling the axial movement of the mobile part, thecylindrical portion of the barrel being substantially the same length asthe covering cylindrical portion of the mobile part.

Preferably, the covering portion of the mobile part has an innerdiameter corresponding to the outer diameter of the portion of thebarrel that passes through the seat of the flaps.

Preferably, for shotguns, the mobile part at the end of the barrel formsa choke of which the inner diameter decreases in the direction of themouth of the barrel, the covering cylindrical portion covering thebarrel, and the end portion including an inner conical portion having amaximum diameter that is equal to the inner diameter of the barrel andnarrows towards the outlet zone of the barrel.

In another embodiment of the invention (not shown), a second pair offlaps independent of the first ones (or a single flap) is disposed atthe outlet of the cartridge chamber and can be placed on automatic orsemi-automatic weapons; these flaps actuated mechanically by separatedischarge/reloading devices of the weapon serve to prevent combustiongases, the sound wave and the flash exiting via the open breech when thecartridge shell is ejected. This variant, using a second pair of flapsfor automatic or semi-automatic weapons, can be used alone for simplemodification of a weapon without resorting to the silencer, which, forits part, requires at least the replacement or the modification of thebarrel.

In another embodiment of the invention, the silencer device for afirearm, in particular for a rifle or another long or short firearm,includes: at least one closing flap mounted across the axis on thebarrel of the firearm in order to temporarily seal the barrel after aprojectile has passed and prevent the passage of the combustion gasesand the sound wave towards the mouth of the barrel when a shot is fired,

-   -   an actuation unit including a mobile portion of the barrel        downstream from the closing flap for moving the control        mechanism by way of the passage of the projectile;    -   the control mechanism including at least one amplitude lever arm        pivotably mounted on a pivot attached to the barrel, the        amplitude lever arm being coupled to the closing flap, the        actuation unit engaging with the control mechanism to allow a        transverse movement of the closing flap between an open        position, in which the flap allows ammunition to pass towards        the mouth of the barrel, and a closed position, which prevent        the passage of the combustion gases and the sound wave after the        projectile has passed, and an exhaust unit including at least        one exhaust pipe arranged on the barrel upstream from the        closing flap in order to redirect the combustion gases and the        sound wave and allow them to be discharged from the barrel.

In accordance with another aspect, the invention proposes a long orshort firearm, in particular a rifle, comprising a silencer device ofthe aforementioned type, in which the barrel of the firearm comprises afixing system formed by said pivots and a seat disposed across the axisof the barrel, said seat receiving said closing flap mechanism so as tofix the silencer device to the barrel removably.

To this end, in accordance with a further aspect, the invention proposesa method for silencing a firearm, in particular a rifle or for anotherfirearm, when a shot is fired, the method comprising the followingsteps:

-   -   temporarily sealing the barrel after a projectile has passed and        preventing the passage of the combustion gases and the sound        wave towards the mouth of the barrel when a shot is fired, by        means of at least one closing flap mounted across the axis on        the barrel of the firearm,    -   moving a control mechanism by way of the action of the passage        of the projectile in a mobile barrel portion;    -   the control mechanism including at least one amplitude lever arm        pivotably mounted on pivots attached to the barrel, each        amplitude lever arm being coupled to a separate closing flap,    -   generating, by means of the actuation unit and the control        mechanism, a transverse movement of the closing flap between an        open position, in which the flap allows a projectile to pass        towards the mouth of the barrel, and a closed position, which        prevents the passage of the combustion gases and of the sound        wave after the projectile has passed, and    -   redirecting the combustion gases and the sound wave and allowing        them to be discharged from the barrel by means of an exhaust        unit including at least one exhaust pipe disposed on the barrel        and upstream from the closing flap.

Thus, in order to achieve this aim, the barrel is temporarily sealedwith the aid of one or more closing flaps just after the passage of theprojectile, and the combustion gases and the sound wave are redirectedtowards an expansion space for their final processing.

SOUND WAVES WHEN A SHOT IS FIRED

There are, in principle, three sound waves which are generated by afired shot. Two are produced within the barrel, and the third one isproduced outside the barrel.

Inside the barrel the first sound wave is that produced by thecombustion of the explosive charge. The second is the famous “bang”produced by the projectile as it passes the sound barrier, which is thecase for approximately 96% of ammunition. This “bang” occurring insidethe barrel is not certain, but assumed; however, it is certain that itis never produced outside the barrel. To the human ear these two soundwaves are perceived to be a single noise. The third sound wave isproduced with the exit of the projectile from the barrel, similar to awhiplash in the air. Said third sound has a magnitude of from 72 to 80dB and cannot in any way be controlled.

The combustion of the powder gives off an immediate heat of from 2500 to3000° C., as well as 2-2.5 grams of gas which, not compressed, give avolume of approximately 1.12 m³.

The sound wave produced by the combustion and the bang moves (at thistemperature) at approximately 1500-1800 m/s (immediate speed) whereasthe projectile is still in a phase of acceleration and reaches itsmaximum speed only after having travelled a distance of approximately 60cm.

According to the invention, the sound wave has three properties ofinterest: the first is that, when it encounters an obstacle, it rebounds(echo phenomenon), the second is that it does not propagate in a vacuum,and the third and most interesting for the silencer device of thepresent invention is that it has a short life. It is therefore notpossible in any way to store a sound wave: by preventing it frompropagating it disappears.

The sound wave does not stick to the projectile. Upon striking it, thewave rebounds to the rear of the breech, which for its part returns thewave towards the projectile. It passes back and forth endlessly betweenthese two obstacles, until the projectile exits via the mouth of thebarrel, at variable speed depending on the temperature of the mediumthrough which it passes and that of the gases carrying it. The soundwave then propagates in the air at the exit of the barrel.

Whereas a conventional silencer of the aforementioned kind, alsoreferred to as a noise regulator, endeavours to mechanically reducenoise, the silencer of the present invention allows it to completelydeplete naturally and manages to eliminate it completely by keeping thesound inside the barrel for a very short time.

In addition, the silencer device for a firearm of the present inventionis advantageous in terms of weight (approximately 50 g in total),manufacturing cost and effectiveness. According to the invention, thesound wave produced within the barrel is completely destroyed because itis retained behind the flap(s).

Solely the noise produced by the sound wave generated outside the barrelthus remains.

In fact, the silencer device for a firearm of the present inventionallows the sound wave to deplete naturally and above all deals with thepressure generated by the gases. If there were no escape provided by anexhaust pipe, the gases would remain compressed within the barrel,keeping the flap(s) closed. They would expand solely at the opening ofthe rifle, without posing any danger but with some disadvantages.

In accordance with the invention it has been deemed preferable toincrease the inner volume of the barrel by one or two exhaust pipes.This additional volume lowers the pressure of the gases and allows theflap(s) to open by means of the system of return springs, and allows thegases to escape naturally simultaneously in a forwards direction and viathe end of the exhaust temporarily sealed by flaps of a size similar tothose arranged on the barrel. The reduction in the pressure of the gasesinside the barrel is also brought about by the quick cooling of saidgases.

BRIEF DESCRIPTION OF THE FIGURES

Further features and advantages of the invention will become clear fromreading the following detailed description. Also, in order to provide aclearer understanding of the invention, several preferred embodimentswill be described hereinafter by way of example, with reference inparticular to the accompanying figures, in which:

FIG. 1 shows a silencer device for a firearm in an embodiment of theinvention,

FIG. 2 is a partial side view in cross-section of the device as shown inFIG. 1,

FIG. 3 is a side view of the device as shown in FIG. 1 prior to beingassembled,

FIG. 4 is a partial side view of the part 38 of the device as shown inFIG. 1,

FIG. 5 is a partial side view in cross section of the part 38 of thedevice as shown in FIG. 1,

FIG. 6 is a partial side view of the device as shown in FIG. 1,

FIG. 7 is a partial side view of the device as shown in FIG. 1,

FIG. 8 shows a silencer device for a firearm in another embodiment ofthe invention,

FIG. 9 is a partial side view in cross-section of the device as shown inFIG. 8,

FIG. 10 is a partial side view in cross-section of the device as shownin FIG. 8,

FIG. 11 shows a silencer device for a firearm in another embodiment ofthe invention,

FIG. 12 is a partial side view of the device as shown in FIG. 11,

FIG. 13 is a side view of an exhaust unit of the silencer device for afirearm in an embodiment of the invention.

EMBODIMENTS OF THE INVENTION

The present invention is described on the basis of particularembodiments and with reference to the figures, but the invention is notlimited thereto. The drawings or figures described are merely schematicand are not limiting.

FIG. 1 shows a silencer device for a firearm in an embodiment of theinvention.

In accordance with the preferred embodiment shown in FIG. 1, two closingflaps (10) are mounted across the axis on the barrel of the firearm inorder to temporarily seal the barrel after a projectile has passed andto prevent the passage of the combustion gases and the sound wavetowards the mouth of the barrel (42) when a shot is fired.

The closing flaps (10) are disposed in a seat (37) placed across theaxis of the barrel and are of a predetermined length and are slightlyoffset from one another along the axis of the barrel, such that theypartially overlap one another in the closed position without contactingone another.

The control mechanism (6) includes two amplitude lever arms (8) mountedon pivots (7) so as to allow a transverse movement of the two closingflaps (10) between an open position, in which the flaps (10) allow aprojectile to pass towards the mouth of the barrel, and a closedposition, which prevents the passage of the combustion gases and thesound wave after the projectile has passed.

The exhaust unit (11) includes two exhaust pipes (11) arranged upstreamfrom the closing flaps (10) in order to redirect the combustion gasesand the sound wave and allow them to be discharged from the barrel (42).

The control mechanism (6) is positioned upstream from the flaps (10).

The control mechanism (6) actuates the amplitude lever arms (8), whichclose the flaps (10), thus allowing the gases to be discharged via thepipes (11). The flaps (10) (and their seat 37) are preferably disposedacross the axis of the barrel (42) and are of a predetermined length andare slightly offset from one another along the axis of the barrel, suchthat they partially overlap one another in the closed position withoutcontacting one another.

Advantageously, each flap (10) includes an opening for receiving the endof the amplitude lever arm (8) so as to transmit the pivoting movementof the amplitude lever (8) and actuate the flap (10) in a transversedirection relative to the axis of the barrel (42). The element (6) ofthe actuation mechanism is moved in a direction generally parallel tothe axis of the barrel (42).

Preferably, the control mechanism (6) includes a guide ring (6) that iscapable of sliding over the barrel and is connected to the rod of themobile portion of the barrel (31) so as to transmit the movement to thelever arms (8).

Advantageously, as can be seen for example in FIGS. 1-2, the guide ring(6) also includes two support parts disposed laterally to the axis ofthe barrel (42), each forming an elongate opening for receiving the endof one of the lever arms (8) and including an angled-edge (rectilinearor curvilinear) guide surface directed towards the flaps (10) forenabling the actuation of the lever arms (8) pivoting on the pivots (7)in order to close and open the flaps (10).

Alternatively, in an embodiment not shown, the guide ring (6) includestwo wedge-shaped support parts disposed laterally to the axis of thebarrel (42) and having an angled-edge (rectilinear or curvilinear)surface directed towards the flaps (10) for enabling the actuation ofthe lever arms (8) pivoting on the pivots (7) in order to close and openthe flaps (10).

The passage of the projectile in the mobile portion of the barrel (31)pushes said portion forwards, thus pulling, by means of the rod, thering (6) and transmitting the movement thereto, which allows this ringto actuate the lever arms (8) on the pivots (7), which close the flaps(10), the gases thus being diverted towards the exhaust (11).

The entire mechanism could be protected by a standard-use cover andcould prevent damage when used with a firearm; however, this will bedependent on the weapon in question and its components. Since the coveris not essential for correct functioning, it will not be described ingreater detail.

The two flaps (10) close the barrel once the bullet has passed through,such that the sound wave and the gases are redirected towards anexpansion space. A second pair of flaps can be used to close the barrelfrom the outset in the case of automatic or semi-automatic weapons. Thecontrol ring (6) is actuated by the passage of the projectile after theflaps in a small portion (31) of the barrel which is mobile andconnected to the control ring (6) by a rod. This portion (31) of thebarrel (of the same calibre as the barrel) is placed after the flaps(10) at a distance therefrom equal to the length of the body of theprojectile (without any potential tip). This part (31) is mobile andmoves by approximately 0.5 mm, which serves to close the flaps (10)immediately after the passage of the bullet. The proportion of theamplitude levers is dependent on the calibre of the firearm, the maximumbeing 10 for a single-barrel or superposed .12 calibre, and 20 for ajuxtaposed (lateral) .12 calibre, because for this firearm it isnecessary to have a single flap (10). The parts (31, 6, 8 and 10) arerepositioned into the normal position by a return spring (32).

As can be seen in FIG. 2, the control mechanism (6) comprises atransmission rod and the mobile portion (31) includes a couplingassembly (34-36) for moving the control ring (6). The coupling assembly(34-36) comprises a connection arm (34) fixed to the mobile portion (31)by a connection screw (35) and attached to the transmission rod by abolt and nut (36).

As can be seen in further detail in FIGS. 6 and 7, which are partialside views of the device as shown in FIG. 1, the elongate opening formedin the transmission rod allows axial adjustment of the position of therod relative to the connection arm (34) and to the mobile portion (31)by tightening of the nut (36).

The transmission rod is positioned in a direction generally parallel tothe axis of the barrel defining the direction of the projectile. As theprojectile passes a defined point, the mobile portion (31) is actuatedaxially and allows the transmission of the movement to the controlmechanism (6) by coupling to the coupling assembly (34-36) and to thetransmission rod.

The control mechanism (6) having the rod is connected to the returnspring (32) disposed on an anchor (33) for attachment to the barrel. Asthe axial force on the part (31) decreases, the rod and the controlmechanism (6) resume their initial position thanks to the return spring(32).

SPECIFIC DETAILS

In this version, the device can be incorporated in the weapon at thetime of its manufacture, or can be added to an existing weapon in theform of extensions to the existing barrel(s), or in the form of anextension of the barrel(s) after shortening thereof. The addition ismade by screwing, soldering, a nested configuration or any other means.

1. Device Incorporated in the Weapon

In the case in which the device is incorporated in the weapon, as can beseen in FIGS. 1 to 3, the part (31), as an extension of the barrel, ismobile, its start being situated after the flaps (10) at a precisedistance corresponding to the length of the body of the projectile. Whenpassing through said part, the projectile imparts an axial movementthereon, which actuates the entire device and causes the flaps (10) toclose completely and immediately. The gases and the sound wave are thusredirected via the exhaust (11) in order to be processed. The projectilecontinues its course in the portion (38) of the weapon, i.e. theextension of the barrel.

Since the axial force produced on the part (31) by the projectile is fargreater than the needs of the device, it is possible to reduce saidforce by carefully increasing the diameter of said part (31), which isin principle of the same calibre as the barrel, or by adding a spring(not shown) around the straight portion of the part (31) that re-entersthe part (38), or both.

It should be noted that the part (31) does not contact the end of thepart (38) that receives it.

As can be seen in FIG. 3, the mobile part (31) is in the middle of thebarrel. This mobile part (31) is joined to the portion of the barrel(42) exiting the seats (37) of the flaps (10) and the end portion (38)of the barrel. This mobile part (31) is cylindrical and comprises aninner bore capable of allowing the passage of a bullet. The interior ofthe barrel in which the projectile moves is deconstructed into threeportions (42, 31, 38) which must be perfectly aligned.

The cylindrical mobile part (31) includes a covering portion and acovered portion separated by a shoulder.

In its covering cylindrical portion, the mobile part (31) covers thebarrel (42), and in its covered cylindrical portion it is covered by thefinal portion of the barrel (38).

The length of the portion of the barrel (42) that passes through theseat (37) of the flaps (10) has a fixed length equal to the length of abullet for this type of weapon. If the portion of the part (31) were tobe covered instead of being covering, it could then recede inside theportion (42) and thereby prevent the flaps (10) from closing correctly.

In its covered portion, the part (31) reproduces the portion (42) thatexits from the flaps (10), and is covered in turn. The part (38) that ismounted on the seats (37) of the flaps (10) will contain the part (31)in its entirety (FIGS. 2 and 5).

As can be seen in FIGS. 2 and 5, the final portion (38) of the barrelcomprises a receptacle including a first cylindrical portion forreceiving the covering portion of the mobile part (31) and a secondcylindrical portion of a smaller diameter for receiving the coveredportion of the mobile part (31). The first cylindrical portion and thesecond cylindrical portion of the final portion (38) are separated by ashoulder.

The first cylindrical portion of the final portion (38) is longer thanthe covering cylindrical portion of the mobile part (31) so as to allowthe axial movement of the mobile part (31). The second cylindricalportion of the final portion (38) can be the same length as the coveredcylindrical portion of the mobile part (31). The final portion (38) ofthe barrel can be very short.

The covering portion of the mobile part (31) has an inner diametercorresponding to the outer diameter of the portion of the barrel (42)that passes through the seat (37), and has an outer diametercorresponding to the inner diameter of the first cylindrical portion ofthe final portion (38).

The covered portion of the mobile part (31) has an inner diametercorresponding to the inner diameter of the portion of the barrel (42)that passes through the seat (37), and has an outer diametercorresponding to the inner diameter of the second cylindrical portion ofthe final portion (38).

As can be seen in FIG. 3, the assembly can be performed in particularsuch that the device (31, 37, 38) is incorporated in the weapon at thetime of its manufacture.

The seat (37) of the flaps (10) is fixed to the portion 38 of theweapon, i.e. the extension of the barrel. The straight portion of themobile part (31) is inserted between the seat (37) and the part 38. Theconnection arm (34) and the part (35) are added to the part 31 afterassembly.

As can be seen in FIGS. 4 and 5, the part (38) of the device as shown inFIG. 1 forms the end portion (38) of the barrel and includes a portionintended for assembly on the seat (37) of the flaps (10) and forreceiving the mobile part (31).

By way of example, in the case of a .30 calibre Blaser rifle, withparticular reference to FIGS. 1 to 3, the specific dimensionsrecommended for the device incorporated in the weapon can be as follows:

30 Calibre Blaser Rifle

-   -   Diameter of the projectile: 7.85 mm    -   Inner diameter of the barrel at the height of the grooves: 7.6        mm    -   Outer diameter of the barrel 15 mm    -   Length of the bullet body (without the pointed portion): 20 mm

Portion of the Barrel (42) That Exits From the Seat of the Flaps (37)

-   -   Length: 20 mm    -   Inner diameter 7.6 mm    -   Outer diameter: 10 mm    -   Mobile part (31)    -   Total length 24 mm

Covering Portion

-   -   Length: 20 mm    -   Outer diameter: 12 mm    -   Inner diameter: 10.2 mm

Covered Portion

-   -   Length: 4 mm    -   Outer diameter: 10.2 mm    -   Inner diameter: 7.6 mm

Portion 38

-   -   Outer diameter: 15 mm (irrelevant length)    -   Inner diameter of the first portion: 12.2 mm over 23 mm length        (the part 31 will thus have a stroke of 3 mm)    -   Inner diameter of the second portion: 10.2 mm over 4 mm length    -   Inner diameter of the final portion: 7.6 mm to the end

2. Device Added to Existing Weapons

In the case in which the device is added to existing arms, it isnecessary to distinguish between BB guns and shotguns.

Indeed, in BB guns the calibre of the barrel is the same over its entirelength, whereas for the majority of shotguns the barrel ends with anarrowing referred to as a choke, of varying dimensions depending on thedesired performance.

In shotguns it is well known that when a cartridge is detonated, theimpact of the lead has a certain dispersion, which increasesproportionally to the distance at which the impact occurs.

This dispersion can be influenced by the use of what is known as achoke. In particular, various types of chokes or throttles can bemounted on the barrels of a rifle in order to reduce the exit diameterthereof so as to increase the range of the shot and limit the spray ofthe projected leads.

It is therefore clear that, on the one hand, it is necessary to retainthe possibility of choosing a suitable choke in the weapons, and that,on the other hand, if a single final part is used, there will be anincrease of the axial force on this part.

Thus, for BB guns, a configuration as in FIGS. 8 and 9 is used. Forshotguns, however, the configuration of FIG. 10 is used. This versionprovides mobile parts (31) that are interchangeable with appropriatechokes.

The alternative for shotguns is to use a mini-part (38) at the outer endof which a choke of the aforementioned type can be screwed on (FIG. 10),thus forming a throttling or narrowing to be mounted on the barrel inorder to reduce the exit diameter, so as to increase the range of theshot and limit the spray of the projected shot material.

FIGS. 8, 12 and 9 (exploded) show a mobile part (31) mounted at thefinal portion of the barrel. This is the same configuration for bulletsand for chokes. Whereas for BB guns the portion (31) is cylindrical andrather short, for shotguns the portion (31) has the forms, theconfigurations and the length of a traditional choke (FIG. 10).

As can be seen in FIGS. 8 and 9, the mobile part (31) is at the end ofthe barrel. This mobile part (31) is mounted on the portion of thebarrel (42) exiting from the seats (37) of the flaps (10). This mobilepart (31) is cylindrical and comprises an inner bore capable of allowingthe passage of a bullet. The interior of the barrel in which theprojectile moves is deconstructed into two portions (42, 31) which mustbe perfectly aligned.

The cylindrical mobile part (31) includes a covering portion and a finalportion separated by a shoulder.

In its covering cylindrical portion, the mobile part (31) covers thebarrel (42), and in its final cylindrical portion it forms the mouth ofthe barrel.

In its final portion, the part (31) reproduces the portion (42) thatexits from the flaps (10). The part (31) is mounted on the portion (42)that exits from the flaps (10) (FIG. 9).

As shown in FIG. 9, the covering portion of the mobile part (31)comprises a receptacle including a cylindrical portion capable ofreceiving the cylindrical portion of the final portion (42) of thebarrel and of enabling the axial movement of the mobile part (31). Thecylindrical portion of the final portion (42) can be the same length asthe covering cylindrical portion of the mobile part (31). The finalportion (38) of the barrel can be very short.

The covering portion of the mobile part (31) has an inner diametercorresponding to the outer diameter of the portion of the barrel (42)that passes through the seat (37).

By way of example, in the case of a .30 calibre Blaser rifle, withparticular reference to FIGS. 8 and 9, the specific dimensionsrecommended for the device added to the existing weapon can be asfollows:

30 Calibre Blaser Rifle

-   -   Diameter of the projectile: 7.85 mm    -   Inner diameter of the barrel at the height of the grooves: 7.6        mm    -   Outer diameter of the barrel 15 mm    -   Length of the bullet body (without the pointed portion): 20 mm

Portion of the Barrel (42) That Exits From the Seat of the Flaps (37)

-   -   Length: 20 mm    -   Inner diameter 7.6 mm    -   Outer diameter: 10 mm

Mobile part (31)

-   -   Total length 24 mm    -   Outer diameter 15 mm

Covering Portion

-   -   Length: 20 mm    -   Inner diameter: 10.2 mm

Final Portion

-   -   Length: 4 mm    -   Inner diameter: 7.6 mm

As shown in FIG. 10 the mobile part (31) is at the end of the barrel andforms a choke used in particular for shotguns, the choke forming apassage for the lead, which extends into the extension of the barrel andthe inner diameter of which reduces in the direction of the mouth of thebarrel. As can be seen in FIG. 10, the cylindrical mobile part (31)includes a covering portion and a final portion separated by a shoulder.

In its covering cylindrical portion, the mobile part (31) covers thebarrel (42), and in its final portion forming the mouth of the barrel itincludes a conical portion having a maximum diameter that is equal tothe inner diameter of the barrel and narrows towards the outlet zone.

As shown in FIG. 11, for all the embodiments, it is possible to increasethe resistance of the part (31) to axial movement by means of returnsprings (40) placed between an element (41) of the part (31) and a rod(39) fixed to the seat (37) of the flaps (10) so as to allow the part(31) to resist axial movement and resume its initial position. Theversion of FIG. 11 is similar to FIGS. 8, 12 and 9 and shows areinforced version of the portion (31) in a final position.

It should be noted that the bullet length of shotguns correspondsapproximately to the length of the wad. This is dependent on theammunition employed and the length of the rifle chamber. The length ofthe latter is 68 mm (virtually obsolete), 70 mm, 76 mm and 82 mm.

It goes without saying that a longer chamber can use shorter cartridges,the opposite being impossible in principle and not recommended. Thelength of a skirted wad for a 70 mm ammunition is approximately 40 mm.The part 6 provides an adjustment mechanism for adaptation.

Incorrect use of ammunition or a malfunction of the device can result indamage. In our tests the use of 2-mm thick aluminium flaps gaveexcellent results. Aluminium flaps intentionally left closed when a shotis fired were passed by the projectiles, even shot material, without anyconsequence.

As can be seen in FIG. 13, in accordance with a preferred embodiment ofthe invention, an expansion space having a timer (22-27) is associatedwith the exhaust pipes (21) for processing the recovered gases andinhibiting the sound wave. Further solutions are possible.

In accordance with the embodiment shown in FIG. 13, the expansion space(27) is coupled to the exhaust pipes (21) and comprises an internal bar(23) moved by the pressure of the gases in order to redirect thesegases. The expansion space 27 receives the gases carried by the recoverypipes (21), which gases enter the expansion space 27 via the opening(22) made in the bar (23) once said bar has been pushed to its endposition and has thus sealed the openings (24). A pressure relief valve(25) is provided (but could be replaced by small holes). As the pressurereduces, the bar resumes its starting position owing to the returnspring (26) and the gases are discharged via the vents (24).

OPERATING PRINCIPLE AND DETAILS

The final aim of the device provided by the invention described here isthat of inhibiting the sound wave produced by the firing of theammunition (rifle shot).

This stopper intended to inhibit the sound wave produced by the firingof the ammunition (rifle shot) prevents the combustion gases and soundwaves from exiting via the mouth of the barrel by diverting them towardsa suitable processing zone, whilst leaving the properties of theammunition itself (speed, accuracy, etc.) unaffected.

Principle

a) a sound wave has a short life;

b) it cannot be preserved;

c) it is stopped by any obstacles (in which case it rebounds—resonance),whether said obstacle is stationary or is moving;

d) it does not propagate in a vacuum; when a shot is fired, two soundwaves are in principle generated within the barrel, one each by thefollowing:

1) the detonation produced by the explosion;

2) the typical “bang” when the sound barrier is passed;

the sound waves follow the projectile; although the speed of sound in agaseous medium is variable (it can reach very high values depending inparticular on the temperature of the gases), the sound wave does notstick to the projectile within the barrel; if the speed of the wave isgreater than that of the projectile, the wave moves back and forthwithin the barrel. The speed of the projectile may vary between 250 and950 m/s depending on the calibre and type of ammunition.

Practical Application

Recognising that the maximum speed of a projectile is reached after 60cm of travel in practice, after this distance an opening of suitablesize to redirect the gases is made in the barrel, and, just after thisopening, a transverse rail having a left-hand flap and a right-hand flap(or lower and upper flaps) is incorporated into the barrel, each flapintended to seal a transverse half of the barrel by superposition. Thetwo flaps are actuated by an amplitude lever. The lever(s) of each flapis/are implemented by a control moved by the passage of the projectile,which pushes a mobile portion of the barrel forwards.

This is effective for weapons referred to as long weapons; for shortweapons the position of the device is selected accordingly.

The mechanism is preferably formed of:

i) a mechanical or hydraulic closure valve having one flap (solid orhinged) or preferably having two juxtaposed flaps (two halvesoverlapping one another, improved solution because it is quicker),having a diaphragm (of the camera shutter type), having a blade; returnspring;

ii) a device for control and kinetic motivity by way of the thrust ofthe projectile;

iii) a sealed expansion space;

iv) possibly an autonomous device for resetting; the disc valve (oneflap or dual flaps) closes the barrel just after the projectile haspassed through, after which said projectile will have travelled between0.5 and 1 mm after the flaps, this distance being freely selected by theamplitude coefficient applied to the levers.

The tests performed successfully were:

A) neutralisation of the gases in the expansion space;

B) closure of the barrel after passage of the projectile by means of adisc valve;

In summary, the following will be provided:

i) one closing flap or two opposite closing flaps on two slightly offsetaxes, so as to avoid contact;

ii) control device (kinetic motivity by way of the thrust of theprojectile) with spring return;

iii) amplitude lever mechanisms on each side;

iv) opening(s) for redirecting the gases;

all of the measurements of the components must be defined depending onthe calibre of the weapon and the maximum length of the projectile,minus the pointed portion before the shoulder if applicable;

the total amplitude factor established by the levers will be defineddepending on the calibre; the residual noise is that created by theprojectile flying through the air.

In accordance with the invention, the motivity of the device is assuredsolely by the passage of the bullet in the part (31) that is mobile(displacement in the order of max. one millimetre).

In all firearms, the cross section of the barrel is very slightlysmaller than the calibre of the bullet, so as to assure a lateraltightness to best utilise the pressure of the gases. Thus, as soon asthe bullet, which is travelling from left to right in relation to thedrawings (for example FIG. 2), has passed the flaps (10) over its entirelength, it enters the mobile portion of the barrel (31), imparting anaxial forward movement thereon. The mobile part (31) actuates thecontrol ring (6) which, by also moving from left to right, closes theflap(s) (10) by means of the lever arms (8). The gases and the soundwave are thus deflected by the exhaust(s) (11). The parts (31, 6, 8 and10) resume the initial position thanks to the return spring (32).

According to the invention, either the device is incorporated in thebarrel during its manufacture (in which case the device is located wellupstream from the mouth of the barrel, and therefore a barrel end isadded after the part (31) or the part 38)—as shown by the drawings (FIG.2)—or the device is attached to the end of the barrel on the mouth side(FIG. 8), extending the existing weapon or replacing a portion of theexisting weapon, after having shortened it consequently. This additioncan be made by a number of methods: soldering, screwing, bayonetconnection, etc.).

In addition, the proportion of the amplitude arms is directly dependenton the calibre of the weapon: 1 to 4 for 8 mm (bullet), 1 to 10 for a.12 calibre (shot material) and is thus fixed.

Processing of the Gases and Sound Wave

The closing mechanism consists of lever arms (8) actuated by a part (6),the shape of which can be variable.

Once the projectile has passed the flaps, these close directly behindand the gases are directed towards one or two exhaust pipes leading toan expansion space having a timer. The gases carried by the recoverypipes (21) enter the expansion space via the opening (22) made in thebar (23) once said bar has been pushed to its end position and has thussealed the openings (24). A pressure relief valve (25) is provided (butcould be replaced by small holes). As the pressure reduces, the barresumes its starting position owing to the spring (26) and the gases aredischarged via the vents.

OPERATING SEQUENCE

Once it has entirely and fully passed the open flaps, the projectilepenetrates a mobile portion of the barrel (31), pushing it forward.Because the rod of this portion (31) is connected to the ring (6), itpulls the ring forward, with the result of actuating the lever arms (8)on the pivots (7), which close the flaps (10), the gases thus beingdiverted to the exhaust (11) and then processed in the expansion space(27).

In accordance with a preferred embodiment of the invention, for a longfirearm, the following should therefore be noted:

Exhaust openings should be made after a distance of 60 centimetres, towhich the expansion space will be applied tightly, said openings beingof a size suitable to contain the combustion gases; this expansion space(27) could have any shape and could be made of any material (solid orresilient); it could be applied at any point of the weapon (for examplelaterally on the barrel or beneath);

Just downstream from these openings there is a flap support (10)incorporated in the barrel during its manufacture or as a modificationthereto; the flap device is actuated by a linkage.

The movement of the device as a whole is controlled by the thrustexerted by the projectile on the mobile portion of the barrel (31).

The amplitude coefficient is calculated depending on the calibre in sucha way that the flaps close immediately after the passage of theprojectile, allowing it to advance by less than a millimetre.

NOMENCLATURE

No. Part name

-   6 control ring-   7 pivots-   8 lever arms 10 flaps-   11 exhaust pipes-   31 mobile portion-   32 return spring-   33 spring anchoring-   34 connection rod or arm-   35 connection screw-   36 bolt and nut-   37 flap seats-   38 final portion with barrel-   39 reinforcement rod-   40 retention spring-   41 reinforcement anchoring-   42 barrel-   21 exhaust junction-   22 opening on axis 23 axis and flaps-   24 vent openings-   25 pressure relief valve-   26 return spring-   27 expansion space

FINAL CONSIDERATIONS

All the parts, their form and their positions can vary withoutlimitation. The recovery or exhaust pipes can be reduced to just one andare not necessarily tubular, the expansion space can be of a differentshape, and the control mechanism 6 shown by a full circular ring couldbe in the form of a circular arc, etc.

The present invention is not in any way limited to the embodimentdescribed by way of example and shown in the drawings. Numerousmodifications of the details, shapes and dimensions could be madewithout departing from the scope of the invention. The present inventionhas been described with reference to specific embodiments which arepurely illustrative and should not be considered limiting. The referencenumbers in the claims do not limit the scope thereof.

1. A silencer device for a firearm, in particular for a rifle or anotherlong or short firearm, comprising: a flap mechanism (10) comprising atleast one closing flap (10) mounted across the axis on the barrel (42)of the firearm in order to temporarily seal the barrel after ammunitionhas passed and to prevent the passage of the combustion gases and thesound wave towards the mouth of the barrel when a shot is fired, anactuation unit (31, 34, 35) including a mobile portion (31) disposedaxially on the barrel of the firearm so as to move a control mechanism(6), the axially mobile portion (31) having an inner bore suitable forallowing the passage of ammunition, the control mechanism (6) includingat least one amplitude lever arm (8) pivotably mounted on a pivot (7)attached to the barrel, each amplitude lever arm (8) being coupled to aseparate closing flap (10), the mobile actuation unit (31, 34, 35)engaging with the control mechanism (6) to allow a transverse movementof said at least one closing flap (10) between an open position, inwhich the flap mechanism (10) allows ammunition to pass towards themouth of the barrel (42), and a closed position, which prevents thepassage of the combustion gases and the sound wave after the ammunitionhas passed, and an exhaust unit (11, 21-27) including at least oneexhaust pipe (11, 21) arranged on the barrel upstream from the closingflap mechanism (10) in order to redirect the combustion gases and thesound wave and allow them to be discharged from the barrel.
 2. Thesilencer device according to claim 1, wherein the mobile portion (31) ofthe actuation unit (31, 34, 35) is substantially cylindrical (31) andcan be inserted into a receptacle within the barrel, the mobile portion(31) forming the inner bore of the mobile portion (31) having a diametersubstantially equal to the inner diameter of the barrel (42) so as toallow the passage of the ammunition.
 3. The silencer device according toclaim 1, wherein the control mechanism (6) comprises a transmission rodand the mobile portion (31) includes a coupling assembly (34-36) coupledto the transmission rod so as to move the control mechanism (6) in adirection generally parallel to the axis of the barrel (42).
 4. Thesilencer device according to claim 1, wherein the control mechanism (6)includes a guide and transmission ring (6) capable of sliding over thebarrel, the ring (6) engaging with the rod and the mobile portion (31)so as to transmit the movement to the lever arm (8).
 5. The silencerdevice according to claim 1, wherein the flap mechanism (10) comprisestwo closing flaps (10) that are disposed in a seat (37) placed acrossthe axis of the barrel and are of a predetermined length and areslightly offset from one another along the axis of the barrel (42), suchthat they partially overlap one another in the closed position withoutcontacting one another.
 6. The silencer device according to claim 1,wherein the flap mechanism (10) comprises two closing flaps (10), eachflap (10) includes an opening for receiving the end of the amplitudelever arm (8) so as to transmit the pivoting movement of the amplitudelever (8) and actuate the flap (10) in a transverse direction relativeto the axis of the barrel.
 7. The silencer device according to claim 1,wherein the flap mechanism (10) comprises two closing flaps (10) and theguide ring (6) also includes two support parts disposed laterally to theaxis of the barrel, each forming an elongate opening for receiving theend of one of the lever arms (8) and for enabling the actuation of thelever arms (8) pivoting on the pivots (7) in order to close and open theflaps (10).
 8. The silencer device according to claim 1, wherein thecontrol mechanism (6) includes at least one first return spring (32)associated with the guide ring (6) such that said guide ring can resumeits initial position, lowering the pressure of the gases.
 9. Thesilencer device according to claim 1, wherein the exhaust unit (11,21-27) also comprises an expansion space (27) connected to said at leastone exhaust pipe (11, 21) so as to receive the gases transported by saidat least one exhaust pipe (11, 21), the expansion space (27) includingvents (24) for discharging the combustion gases and the sound wave fromthe expansion space (27).
 10. The silencer device according to claim 9,wherein the expansion space (27) comprises an inner pipe (23) connectedto flaps capable of sealing the vents (24), and wherein the gases enterthe expansion space (27) via an opening (22) made in the inner tube (23)once said tube has been pushed to its end position and has thus sealedthe vents (24), and, as the pressure reduces, the inner tube (23)resumes its starting position owing to a return spring (26), thusallowing the combustion gases and the sound wave to be discharged fromthe expansion space (27) via the vents (24).
 11. The silencer deviceaccording to claim 1, wherein the mobile portion (31) of thesubstantially cylindrical actuation unit (31, 34, 35) joins a portion ofthe barrel (42) that passes through the seat (37) of the closing flapmechanism (10) and an end portion (38) of the barrel, and includes acovering portion and a covered portion separated by a shoulder, thecovering cylindrical portion being able to cover the portion of thebarrel (42) that passes through the seat (37) of the flap mechanism(10), and the covered cylindrical portion being able to be covered bythe end portion (38) of the barrel.
 12. The silencer device according toclaim 11, wherein the final portion (38) of the barrel comprises areceptacle including a first cylindrical portion able to receive thecovering portion of the mobile part (31), and a second cylindricalportion of a smaller diameter able to receive the covered portion of themobile part (31), the first cylindrical portion and the secondcylindrical portion of the end portion (38) being separated by ashoulder.
 13. The silencer device according to claim 12, wherein thefirst cylindrical portion of the end portion (38) is longer than thecovering cylindrical portion of the mobile part (31) so as to allow theaxial movement of the mobile part (31), the second cylindrical portionof the end portion (38) being substantially the same length as thecovered cylindrical portion of the mobile part (31).
 14. The silencerdevice according to claim 12, wherein the covering portion of the mobilepart (31) has an inner diameter corresponding to the outer diameter ofthe portion of the barrel (42) that passes through the seat (37), andhas an outer diameter corresponding to the inner diameter of the firstcylindrical portion of the end portion (38).
 15. The silencer deviceaccording to claim 1, wherein the mobile portion (31) of thesubstantially cylindrical actuation unit (31, 34, 35) forms the endportion of the barrel and includes a covering portion and a finalportion separated by a shoulder, the covering cylindrical portion of themobile part (31) being able to cover a portion of the barrel (42) thatpasses through the seat (37) of the closing flap mechanism (10), and theend portion forming the mouth of the barrel.
 16. The silencer deviceaccording to claim 15, wherein the covering portion of the mobile part(31) comprises a receptacle including a cylindrical portion capable ofreceiving the cylindrical portion of the barrel (42) that passes throughthe seat (37) of the flap mechanism (10) and of enabling the axialmovement of the mobile part (31), the cylindrical portion of the barrel(42) being substantially the same length as the covering cylindricalportion of the mobile part (31).
 17. The silencer device according toclaim 15, wherein the covering portion of the mobile part (31) has aninner diameter corresponding to the outer diameter of the portion of thebarrel (42) that passes through the seat (37) of the flap mechanism(10).
 18. The silencer device according to claim 15, wherein the mobilepart (31) at the end of the barrel forms a choke of which the innerdiameter decreases in the direction of the mouth of the barrel, thecovering cylindrical portion covering the barrel (42), and the endportion including an inner conical portion of a maximum diameter that isequal to the inner diameter of the barrel and narrows towards the outletzone of the barrel.
 19. A long or short firearm, in particular a rifle,comprising a silencer device according to claim 1, wherein the barrel ofthe firearm comprises a fixing system formed by said pivots (7) and aseat (37) disposed across the axis of the barrel, said seat receivingsaid closing flap mechanism (10) so as to fix the silencer device to thebarrel.
 20. A method for silencing a firearm, in particular a rifle oranother long or short firearm, when a shot is fired, the methodcomprising the following steps: temporarily sealing the barrel afterammunition has passed and preventing the passage of the combustion gasesand the sound wave towards the mouth of the barrel (42) when a shot isfired, by means of a flap mechanism (10) comprising at least one closingflap (10) mounted across the axis on the barrel of the firearm, movingan actuation unit (31) and a control mechanism (6) by way of the thrustof ammunition passing through a mobile portion (31) of the actuationunit (31) disposed axially on the barrel of the firearm, the axiallymobile portion (31) having an inner bore for allowing the passage ofammunition, the control mechanism (6) including at least one amplitudelever arm (8) pivotably mounted on a pivot (7) attached to the barrel,each amplitude lever arm (8) being coupled to a separate closing flap(10), generating, by means of the actuation unit (31) and the controlmechanism (6), a transverse movement of said at least one closing flap(10) between an open position, in which the flap mechanism (10) allowsammunition to pass towards the mouth of the barrel (42), and a closedposition, which prevents the passage of the combustion gases and thesound wave after the ammunition has passed, and redirecting thecombustion gases and the sound wave and allowing them to be dischargedfrom the barrel by means of an exhaust unit (11, 21-27) including atleast one exhaust pipe (11, 21) disposed on the barrel (42) and upstreamfrom the closing flap mechanism (10).